/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.evaluation.value;

import proguard.classfile.ClassConstants;

/**
 * This value factory creates initial values for fields and array elements, with the help of a given value factory. Note
 * that this class itself doesn't implement ValueFactory.
 *
 * @author Eric Lafortune
 */
public class InitialValueFactory {
    private final ValueFactory valueFactory;

    /**
     * Creates a new InitialValueFactory.
     * 
     * @param valueFactory the value factory that will actually create the values.
     */
    public InitialValueFactory(ValueFactory valueFactory) {
        this.valueFactory = valueFactory;
    }

    /**
     * Creates an initial value (0, 0L, 0.0f, 0.0, null) of the given type.
     */
    public Value createValue(String type) {
        switch (type.charAt(0)) {
            case ClassConstants.TYPE_BOOLEAN:
            case ClassConstants.TYPE_BYTE:
            case ClassConstants.TYPE_CHAR:
            case ClassConstants.TYPE_SHORT:
            case ClassConstants.TYPE_INT:
                return valueFactory.createIntegerValue(0);

            case ClassConstants.TYPE_LONG:
                return valueFactory.createLongValue(0L);

            case ClassConstants.TYPE_FLOAT:
                return valueFactory.createFloatValue(0.0f);

            case ClassConstants.TYPE_DOUBLE:
                return valueFactory.createDoubleValue(0.0);

            case ClassConstants.TYPE_CLASS_START:
            case ClassConstants.TYPE_ARRAY:
                return valueFactory.createReferenceValueNull();

            default:
                throw new IllegalArgumentException("Invalid type [" + type + "]");
        }
    }
}
